That car is clearly '71 Ford LTD. The '71 Thunderbird looks different.
My apologies. I don't have any pics of the car on-hand, so I googled 71' ford thunderbird maroon.

After further searching, here is a closer pic, my dad's is all original(even the tires). he rebuilt the carb himself, cleaned the gas tank out with some kind of acid. it sat in storage for more than 20 yrs before when pulled it out.
also the interior is white, not red